.nav {
    height: 80px;
}
.nav .logo-m {
    float: left;
    width: 115px;
    height: 20px;
    background-color: black;
    background:url(../images/logo.png) no-repeat;
    margin: 30px 143px 30px 0px;
}
.nav ul {
    float: left;
}
.nav ul li {
    float: left;
    padding: 0 18px;
    height: 80px;
    line-height: 80px;
}
.nav ul li a {
    font-size: 16px;
}